Quantification of Mitral Regurgitation in Mitral Valve Prolapse by Three-Dimensional Vena Contracta Area: Derived Cutoff Values and Comparison With Two-Dimensional Multiparametric Approach.

BACKGROUND: Echocardiographic grading of mitral regurgitation (MR) in mitral valve prolapse (MVP) is challenging. Three-dimensional (3D) vena contracta area (VCA) has been proposed as a valuable method. However, data defining the cutoff values of severity and validation in the subset of patients with MVP are scarce. The aim of this study was to validate the 3D VCA by 3D color-Doppler transesophageal echocardiography (TEE) in patients with MVP and to define the cutoff values of severity grading. The secondary aim was to compare 3D VCA to the effective regurgitant orifice area estimation by proximal isovelocity surface area (EROA-PISA) method. METHODS: A total of 1,138 patients with at least moderate MR who underwent TEE were included. Three-dimensional VCA was measured, and the cutoff value and area under the curve (AUC) for the prediction of severe MR were estimated by receiver operating characteristic curve using a guideline-suggested multiparametric approach as the reference standard. In a subgroup of patients, 3D regurgitant volume (RV) and 3D fraction were calculated from mitral and left ventricular outflow tract stroke volumes to further validate 3D VCA against a 3D volumetric reference standard. RESULTS: The optimal 3D VCA cutoff value for predicting severe MR was 0.45 cm2 (specificity, 0.87; sensitivity, 0.90) with an AUC of 0.95 using a multiparametric approach as reference. Three-dimensional VCA had a good linear correlation with EROA-PISA (r = 0.62, P < .05) with larger values compared to EROA-PISA (0.63 cm2 vs 0.44 cm2, P < .05). A cutoff of 0.50 cm2 (AUC of 0.84; sensitivity, 0.78; specificity, 0.78) predicts an EROA-PISA of 0.40 cm2. Three-dimensional VCA had a good linear correlation with 3D RV (r = 0.56, P < .01), with an AUC of 0.86 to predict a 3D fraction >50%. CONCLUSIONS: The present study suggests 0.45 cm2 as the best cutoff value of 3D VCA to define severe MR in patients with MVP, showing an optimal agreement with the reference standard multiparametric approach and 3D RV.

Direct oral anticoagulants versus percutaneous left atrial appendage occlusion in atrial fibrillation: 5-year outcomes.

BACKGROUND: LAAO is an emerging option for thromboembolic event prevention in patients with NVAF. We previously reported data on comparison between LAAO and DOAC at two-year follow-up in NVAF patients at HBR (HAS-BLED ≥3). AIMS: Limited data are available on long term follow-up. We aimed to evaluate the efficacy and safety of DOACs versus LAAO indication after 5 years. METHODS: We enrolled 193 HBR treated with LAAO and 189 HBR patients with DOACs. At baseline, LAAO group had higher HAS-BLED (4.2 vs 3.3, p < 0.001) and lower CHADS-VASc (4.3 vs. 4.7, p = 0.005). After 1:1 PSM, 192 patients were included (LAAO n = 96; DOACs n = 96). RESULTS: At 5-year follow-up the rate of the combined safety and effectiveness endpoint (ISTH major bleeding and thromboembolic events) was significantly higher in LAAO group (p = 0.042), driven by a higher number of thromboembolic events (p = 0.047). The rate of ISTH-major bleeding events was similar (p = 0.221). After PSM no significant difference in the primary effectiveness (LAAO 13.3% vs DOACs 9.5%, p = 0.357) and safety endpoint (LAAO 7.5% vs DOACs 7.5%; p = 0.918) were evident. Overall bleeding rate was significantly higher in DOACs group (25.0% vs 13.7%, p = 0.048), while a non-significant higher number of TIA was reported in LAAO group (5.4% vs 1.1%, p = 0.098). All-cause and cardiovascular mortality were higher in LAAO group at both unmatched and matched analysis. CONCLUSION: We confirmed safety and effectiveness of both DOAC and LAAO in NVAF patients at HBR, with no significant differences in thromboembolic events or major bleeding were at 5-year follow-up. The observed increased mortality after LAAO warrants further investigations in RCTs.

Accuracy and Reliability of Left Atrial Appendage Morphology Assessment by Three-Dimensional Transesophageal Echocardiographic Glass Rendering Modality: A Comparative Study With Computed Tomography.

BACKGROUND: Contrast-enhanced computed tomography is the reference-standard imaging technique to assess left atrial appendage (LAA) morphology. The aim of this study was to evaluate the accuracy and reliability of two-dimensional and new three-dimensional (3D) transesophageal echocardiographic rendering modalities in assessing LAA morphology. METHODS: Seventy consecutive patients who underwent both computed tomography and transesophageal echocardiography (TEE) were retrospectively enrolled. The traditional LAA morphology classification system (LAAcs; chicken wing, cauliflower, cactus, and windsock) and a new simplified LAAcs based on the LAA bend angle were used for the analysis. LAA morphology was independently assessed by two trained readers using three different modalities: two-dimensional TEE, 3D TEE with multiplanar reconstruction, and a new 3D transesophageal echocardiographic rendering modality with improved transparency (Glass). The new LAAcs and traditional LAAcs were compared in terms of intra- and interrater reliability. RESULTS: With the new LAAcs, two-dimensional TEE was fairly accurate in identifying LAA morphology (κ = 0.43, P < .05), with moderate interrater (κ = 0.50, P < .05) and substantial intrarater (κ = 0.65, P < .005) agreement. Three-dimensional TEE showed higher accuracy and reliability: 3D TEE with multiplanar reconstruction had almost perfect accuracy (κ = 0.85, P < .001) and substantial (κ = 0.79, P < .001) interrater reliability, while 3D TEE with Glass had substantial accuracy (κ = 0.70, P < .001) and almost perfect (κ = 0.84, P < .001) interrater reliability. Intrarater agreement was almost perfect for both 3D transesophageal echocardiographic modalities (κ = 0.85, P < .001). Accuracy was considerably lower when the traditional LAAcs was used, with 3D TEE with Glass being the most reliable technique (κ = 0.75, P < .05). The new LAAcs showed higher inter- and intrarater reliability compared with the traditional LAAcs (interrater, κ = 0.85 vs κ = 0.49; intrarater, κ = 0.94 vs κ = 0.68; P < .05). CONCLUSIONS: Three-dimensional TEE is an accurate, reliable, and feasible alternative to computed tomography in assessing LAA morphology with the new LAAcs. The new LAAcs shows higher reliability rates than the traditional one.

The long-term clinical course of moderate tricuspid regurgitation.

BACKGROUND: To evaluate the long-term clinical outcome of a cohort of patients suffering from moderate tricuspid regurgitation (TR), regardless of its etiology. METHODS: Clinical and echocardiographic follow-up were assessed in 250 patients diagnosed with moderate TR between January 2016 and July 2020. TR progression at follow-up was defined as TR grade increase to at least severe. The primary endpoint was all-cause death; secondary endpoints were cardiovascular (CV) death and the composite of heart failure (HF) hospitalization plus tricuspid valve (TV) intervention. RESULTS: After a median follow-up of 3.6 years, TR progression occurred in 84 patients (34%). At multivariate analyses, atrial fibrillation (AF, OR 1.81, CI 1.01-3.29, p = 0.045) and right ventricular end-diastolic diameter (RVEDD, OR 2.19, CI 1.26-3.78, p = 0.005) were independent predictors of TR progression. The primary endpoint occurred in 59 patients (24%) and was significantly more frequent in the group with TR progression (p = 0.009). At multivariate analyses, chronic kideney disease (OR 2.80, CI 1.30-6.03, p = 0.009), left ventricular ejection fraction (OR 0.97, CI 0.94-0.99, p = 0.041) and TR progression (OR 2.32, CI 1.31-4.12, p = 0.004) were independent predictors of the primary outcome. Moreover, both the secondary endpoints of CV death and HF hospitalization plus TV intervention were more frequent in the TR progression group (p = 0.001 and p < 0.001, respectively). CONCLUSIONS: Moderate TR progresses in a significant proportion of patients over a long-term follow-up, leading to a worse prognosis. TR progression is an independent determinant of hard clinical events and AF and RVEDD are associated with TR progression.

Prognostic value of right ventricular longitudinal strain in patients with secondary mitral regurgitation undergoing transcatheter edge-to-edge mitral valve repair.

AIMS: To evaluate the prognostic impact of pre-procedural right ventricular longitudinal strain (RVLS) in patients with secondary mitral regurgitation (SMR) undergoing transcatheter edge-to-edge repair (TEER) in comparison with conventional echocardiographic parameters of RV function. METHODS AND RESULTS: This is a retrospective study including 142 patients with SMR undergoing TEER at two Italian centres. At 1-year follow-up 45 patients reached the composite endpoint of all-cause death or heart failure hospitalization. The best cut-off value of RV free-wall longitudinal strain (RVFWLS) to predict outcome was -18% [sensitivity 72%, specificity of 71%, area under curve (AUC) 0.78, P < 0.001], whereas the best cut-off value of RV global longitudinal strain (RVGLS) was -15% (sensitivity 56%, specificity 76%, AUC 0.69, P < 0.001). Prognostic performance was suboptimal for tricuspid annular plane systolic excursion, Doppler tissue imaging-derived tricuspid lateral annular systolic velocity and fractional area change (FAC). Cumulative survival free from events was lower in patients with RVFWLS ≥ -18% vs. RVFWLS < -18% (44.0% vs. 85.4%; < 0.001) as well as in patients with RVGLS ≥ -15% vs. RVGLS < -15% (54.9% vs. 81.7%; P < 0.001). At multivariable analysis FAC, RVGLS and RVFWLS were independent predictors of events. The identified cut-off of RVFWLS and RVGLS both resulted independently associated with outcomes. CONCLUSION: RVLS is a useful and reliable tool to identify patients with SMR undergoing TEER at high risk of mortality and HF hospitalization, on top of other clinical and echocardiographic parameters, with RVFWLS offering the best prognostic performance.

Ratio between right ventricular longitudinal strain and pulmonary arterial systolic pressure: A novel prognostic parameter in patients with severe tricuspid regurgitation.

BACKGROUND: In terms of pathophysiology, tricuspid regurgitation (TR), right ventricular function and pulmonary artery pressure are linked to each other. Our aim was to analyze whether the echocardiography-derived right ventricular free wall longitudinal strain/pulmonary artery systolic pressures (RVFWLS/PASP) ratio can improve risk stratification in patients with severe tricuspid regurgitation (TR). METHODS: In this single-center retrospective study, 250 consecutive patients with severe TR were enrolled from December 2015 to December 2018. Baseline clinical and echocardiographic parameters were collected. Echocardiography-derived TAPSE/PASP and RVFWLS/PASP were evaluated. The primary endpoint was all-cause mortality. RESULTS: Out of 250 consecutive patients, 171 meet inclusion criteria. Patients were predominantly female, with several cardiovascular risk factors and comorbidities. RVFWLS/PASP ≤0.34%/mmHg (AUC 0.68, p < 0.001, sensitivity 70%, specificity 67%) was associated with baseline clinical RV heart failure (p = 0.03). After univariate and multivariate analyses, RVFWLS/PASP, but not TAPSE/PASP, independently correlated with all-cause mortality (HR 0.004, p = 0.02). Patients with RVFWLS/PASP >0.26%/mmHg (AUC 0.74, p < 0.001, sensitivity 77%, specificity 52%) showed higher survival rates (p = 0.02). In addition at 24 months follow-up, the Kaplan-Meyer curves showed patients with RVFWLS >14% & RVFWLS/PASP >0.26%/mmHg had the best survival rate compared to patients without. CONCLUSION: RVFWLS/PASP is independently associated with baseline RV heart failure and poor long-term prognosis in patients with severe TR.

Evolution of interventional imaging in structural heart disease.

Treatments for structural heart diseases (SHD) have been considerably evolved by the widespread of transcatheter approach in the last decades. The progression of transcatheter treatments for SHD was feasible due to the improvement of devices and the advances in imaging techniques. In this setting, the cardiovascular imaging is pivotal not only for the diagnosis but even for the treatment of SHD. With the aim of fulfilling these tasks, a multimodality imaging approach with new imaging tools for pre-procedural planning, intra-procedural guidance, and follow-up of SHD was developed. This review will describe the current state-of-the-art imaging techniques for the most common percutaneous interventions as well as the new imaging tools. The imaging approaches will be addressed describing the use in pre-procedural planning, intra-procedural guidance, and follow-up.

Extracellular volume fraction (ECV) derived from pre-operative computed tomography predicts prognosis in patients undergoing transcatheter aortic valve implantation (TAVI).

AIMS: Transcatheter aortic valve implantation (TAVI) is the treatment of choice for high-risk patients with severe aortic stenosis (AS). A portion of TAVI recipients has no long-term clinical benefit, and myocardial fibrosis may contribute to unfavourable outcomes. We aimed to assess the prognostic value of an interstitial fibrosis marker, extracellular volume fraction (ECV), measured at planning computed tomography (CT) before TAVI. METHODS AND RESULTS: From October 2020 to July 2021, 159 consecutive patients undergoing TAVI planning CT were prospectively enroled. ECV was calculated as the ratio of myocardium and blood pool differential attenuations before and 5 min after contrast administration, pondered for haematocrit. A composite endpoint including heart failure hospitalization (HFH) and death was collected by telehealth or in-person follow-up visits in the 113 patients constituting the final study population. Cox proportional hazards model was used to assess association between ECV and the composite endpoint.Median follow-up was 13 (11-15) months. The composite endpoint occurred in 23/113 (20%) patients. These patients had lower aortic valve mean pressure gradient [39 (29-48) vs. 46 (40-54) mmHg, P = 0.002] and left ventricular and right ventricular ejection fraction [51 (37-69) vs. 66 (54-74)%, P = 0.014; 45 (31-53) vs. 49 (44-55)%, P = 0.010] and higher ECV [31.5 (26.9-34.3) vs. 27.8 (25.3-30.2)%, P = 0.006]. At multivariable Cox analysis, ECV higher than 31.3% was associated to increased risk of death or HFH at follow-up (hazard ratio = 5.92, 95% confidence interval 2.37-14.75, P < 0.001). CONCLUSION: In this prospective observational cohort study, ECV measured at TAVI planning CT predicts the composite endpoint (HFH or death) in high-risk severe AS patients.

Feasibility and reliability of comprehensive three-dimensional transoesophageal echocardiography screening process for transcatheter mitral valve replacement.

AIMS: The procedural planning of transcatheter mitral valve replacement (TMVR) requires a specific imaging assessment to establish patient eligibility. Computed tomography (CT) is considered the reference method. In this setting, data regarding the role of transoesophageal echocardiography (TOE) are lacking. We evaluated the feasibility and reliability of a comprehensive 3D-TOE screening in TMVR candidates. METHODS AND RESULTS: We performed a retrospective observational study including 72 consecutive patients who underwent a pre-procedural CT and 3D-TOE for TMVR evaluation. The measurements of mitral annulus (MA), length of anterior mitral leaflet (AML), native left ventricular outflow tract (LVOT), and predicted neo-LVOT acquired with CT and 3D-TOE were compared using a novel semi-automated software for post processing analysis (3 mensio Structural Heart 10.1-3mSH, Pie Medical Imaging, Bilthoven, Netherlands). The final suitability decision was given by the valve manufacturer based on CT measurements and clinical conditions. Among 72 patients screened, all patients had adequate image quality for 3D-TOE analysis. 3D-TOE and CT measurements for AML length (r = 0.97), MA area (r = 0.90), perimeter (r = 0.68), anteroposterior (r = 0.88), and posteromedial-anterolateral (r = 0.74) diameters were found highly correlated, as well as for native LVOT (r = 0.86) and predicted neo-LVOT areas (r = 0.96) (all P-values <0.0001). An almost perfect agreement between CT and 3DTOE was found in assessing the eligibility for TMVR implantation (Cohen kappa 0.83, P < 0.001). CONCLUSION: 3D-TOE appraisements showed good correlations with CT measurements and high accuracy to predict TMVR screening success.

An Unusual Cause of Stroke: A "Forgotten" Intracardiac Catheter Discovered After 48 Years.

A 48-year-old man with recurrent cerebral ischemic events underwent transesophageal echocardiography to investigate cardioembolic sources because transthoracic echocardiography had spotted a dubious filamentous mass on the mitral valve. A venous umbilical catheter, lost during the hospital stay after his birth, was surprisingly identified in his cardiac chambers. (Level of Difficulty: Beginner.).

Anesthesia-Induced Intraprocedural Downgrading of Mitral Regurgitation During Transcatheter Edge-to-Edge Repair.

During transcatheter edge-to-edge repair (TEER), the reduction of functional mitral regurgitation (FMR) severity, compared with baseline evaluation, is not uncommon. Because the procedural strategies are mainly guided by the location and severity of the regurgitant jets, intraprocedural downgrading (ID) of regurgitation severity could affect the procedural strategy and the results. The aim of this study was to evaluate the prevalence of ID during TEER and to compare early and midterm outcomes in patients with and without ID. All patients with moderate-to-severe or severe FMR who underwent TEER in San Raffaele Hospital between 2018 and 2020 were evaluated in this single-center, retrospective study. ID was defined as mild (1+) or moderate (2+) regurgitation degree during intraprocedural evaluation. The outcomes, assessed at discharge and at 2 years of follow-up, were all-cause mortality, heart failure hospitalization, and recurrence of mitral regurgitation >2+. The final study cohort included 55 patients: 42% presented with ID. At discharge, 85.5% of patients achieved regurgitation reduction to 2+ or less: 100% in patients with ID versus 75% in patients without ID, p <0.009. At 2 years, no significant difference in the incidence of all-cause mortality, heart failure hospitalization, and the recurrence of mitral regurgitation >2+ between patients with ID or without ID was found. In conclusion, ID is frequent during TEER in FMR. No baseline characteristics were found to identify this group of patients. In patients with ID, the combination of live intraprocedural imaging and baseline ambulatory assessment of regurgitant jets seems effective in the procedural guiding to achieve a successful and durable mitral repair.

Molecular basis of cyclic tetra-oligoadenylate processing by small standalone CRISPR-Cas ring nucleases.

Standalone ring nucleases are CRISPR ancillary proteins, which downregulate the immune response of Type III CRISPR-Cas systems by cleaving cyclic oligoadenylates (cA) second messengers. Two genes with this function have been found within the Sulfolobus islandicus (Sis) genome. They code for a long polypeptide composed by a CARF domain fused to an HTH domain and a short polypeptide constituted by a CARF domain with a 40 residue C-terminal insertion. Here, we determine the structure of the apo and substrate bound states of the Sis0455 enzyme, revealing an insertion at the C-terminal region of the CARF domain, which plays a key role closing the catalytic site upon substrate binding. Our analysis reveals the key residues of Sis0455 during cleavage and the coupling of the active site closing with their positioning to proceed with cA4 phosphodiester hydrolysis. A time course comparison of cA4 cleavage between the short, Sis0455, and long ring nucleases, Sis0811, shows the slower cleavage kinetics of the former, suggesting that the combination of these two types of enzymes with the same function in a genome could be an evolutionary strategy to regulate the levels of the second messenger in different infection scenarios.

Structure of the TnsB transposase-DNA complex of type V-K CRISPR-associated transposon.

CRISPR-associated transposons (CASTs) are mobile genetic elements that co-opted CRISPR-Cas systems for RNA-guided transposition. Here we present the 2.4 Å cryo-EM structure of the Scytonema hofmannii (sh) TnsB transposase from Type V-K CAST, bound to the strand transfer DNA. The strand transfer complex displays an intertwined pseudo-symmetrical architecture. Two protomers involved in strand transfer display a catalytically competent active site composed by DDE residues, while other two, which play a key structural role, show active sites where the catalytic residues are not properly positioned for phosphodiester hydrolysis. Transposon end recognition is accomplished by the NTD1/2 helical domains. A singular in trans association of NTD1 domains of the catalytically competent subunits with the inactive DDE domains reinforces the assembly. Collectively, the structural features suggest that catalysis is coupled to protein-DNA assembly to secure proper DNA integration. DNA binding residue mutants reveal that lack of specificity decreases activity, but it could increase transposition in some cases. Our structure sheds light on the strand transfer reaction of DDE transposases and offers new insights into CAST transposition.

Myocardial injury in patients with SARS-CoV-2 pneumonia: Pivotal role of inflammation in COVID-19.

AIMS: Infection by SARS-CoV-2 may result in a systemic disease and a proportion of patients ranging 15%-44% experienced cardiac injury (CI) diagnosed by abnormal troponin levels. The aim of the present study was to analyse the clinical characteristics of a large series of hospitalized patients for COVID-19 in order to identify predisposing and/or protective factors of CI and the outcome. METHODS AND RESULTS: This is an observational, retrospective study on patients hospitalized in two Italian centres (San Raffaele Hospital and Cremona Hospital) for COVID-19 and at least one high-sensitivity cardiac troponin (hs-cTnt) measurement during hospitalization. CI was defined if at least one hs-cTnt value was above the 99th percentile. The primary end-point was the occurrence of CI during hospitalization. We included 750 patients (median age 67, IQR 56-77 years; 69% males), of whom 46.9% had history of hypertension, 14.7% of chronic coronary disease and 22.3% of chronic kidney disease (CKD). Abnormal troponin levels (median troponin 74, IQR 34-147 ng/l) were detected in 390 patients (52%) during the hospitalization. At multivariable analysis age, CKD, cancer, C-reactive protein (CRP) levels were independently associated with CI. Independent predictors of very high troponin levels were chronic kidney disease and CRP levels. Patients with CI showed higher rate of all-cause mortality (40.0% vs. 9.1%, p = 0.001) compared to those without CI. CONCLUSION: This large, multicentre Italian study confirmed the high prevalence of CI and its prognostic role in hospitalized patients with COVID-19, highlighting the leading role of systemic inflammation for the occurrence of CI.

Physical activity volume in patients with arrhythmogenic cardiomyopathy is associated with recurrence after ventricular tachycardia ablation.

PURPOSE: To assess the role of intense physical activity (PA) on recurrence after ventricular tachycardia (VT) ablation in arrhythmogenic cardiomyopathy (ACM). METHODS: We retrospectively analyzed 63 patients with definite diagnosis of ACM who underwent to catheter ablation (CA) of VT. PA was quantified in METs per week by IPAQ questionnaire in 51 patients. VT-free survival time after ablation was analyzed by Kaplan-Meier's curves. RESULTS: The weekly amount of PA was higher in patients with VT recurrence (2303.1 METs vs 1043.5 METs, p = 0.042). The best cutoff to predict VT recurrence after CA was 584 METs/week (AUC = 0.66, sensibility = 85.0%, specificity = 45.2%). Based on this cutoff, 34 patients were defined as high level athletes (Hi-PA) and 17 patients as low-level athletes (Lo-PA). During a median follow-up of 32.0 months (11.5-65.5), 22 patients (34.9%) experienced VT recurrence. Lo-PA patients had a longer VT-free survival, compared with Hi-PA patients (82.4% vs 50.0%, log-rank p = 0.025). At Cox multivariate analysis, independent predictors of the VT recurrence were PA ≥ 584 METs/week (Hi-PA) (HR = 2.61, CI 95% 1.03-6.58, p = 0.04) and late potential (LP) abolition (HR = 0.38, CI 95% 0.16-0.89, p = 0.03). CONCLUSIONS: PA ≥ 584 METs/week and LP abolition were independent predictors of VT recurrence after ablation.

Outcome of left atrial appendage closure using cerebral protection system for thrombosis: no patient left behind.

BACKGROUND: Left atrial appendage (LAA) thrombosis increases the risk of stroke and its management has to be assessed. The aim of the present study is to evaluate short and long-term safety and efficacy of a standardized approach of percutaneous LAA closure (LAAC) routinely using a cerebral protection device (CPD) in patients with LAA thrombosis or sludge (LAAT). METHODS: We prospectively enrolled 14 consecutive patients with atrial fibrillation complicated by LAAT presenting in a high-volume tertiary center. In seven patients (50%) LAAT was found after anticoagulant withdrawal for severe bleedings and in the remaining half LAAT was found despite appropriate anticoagulant therapy. All patients were treated with a standardized interventional approach of LAAC routinely using a CPD and guided by transoesophageal echocardiography. RESULTS: Mean age was 68 ± 14 years and nine patients (64%) were male. Mean CHA2 DS2 -VASc and HAS-BLED scores were 3.3 ± 1.6 and 2.3 ± 1.1, respectively. Six patients (42.8%) presented organized thrombi while eight LAA sludge (57.1%). In 13 patients (92.8%) CPD was positioned through a right radial arterial access. Procedural success was achieved in all patients. In one patient we assisted to embolization of the thrombus during deployment of the device in the absence of neurological consequences. During a mean follow up of 426 ± 307 days, one patient died for non-cardiac cause while no embolic event or major bleeding were reported. CONCLUSION: In an unselected cohort, LAAC with the systematic use of CPD was a feasible, safe and effective therapeutic option for LAAT both acutely and after long-term follow-up.

Transcatheter Edge-to-Edge Repair in COAPT-Ineligible Patients: Incidence and Predictors of 2-Year Good Outcome.

BACKGROUND: COAPT-trial entry criteria are useful to identify patients with better outcomes after transcatheter edge-to-edge repair (TEER). However, up to one-half of real-world patients with secondary mitral regurgitation (SMR) undergoing TEER do not meet these highly selective criteria and no study has formally investigated them. The aim of this study was to evaluate the predictors of good outcome after TEER in COAPT-ineligible patients. METHODS: All consecutive patients with SMR and heart failure (HF) treated with MitraClip at 3 European centres were retrospectively screened. The presence of at least 1 COAPT exclusion criterion was used to define a COAPT-ineligible profile, allowing the inclusion in the study population. Freedom from all-cause death or HF hospitalisation was evaluated at 2-year follow-up (primary end point). RESULTS: A total of 305 patients (47%) had a COAPT-ineligible profile. An overall 58% rate of all-cause death or HF hospitalisation was detected at 2 years. Patients with a single COAPT exclusion criterion experienced fewer adverse events than those with multiple criteria (55% vs 69%). At multivariable Cox regression analysis, New York Heart Association functional class II, younger age (< 75 years), lower serum creatinine (< 2 mg/dL), lower left ventricular end-diastolic volume (< 240 mL), and the absence of hemodynamic instability, atrial fibrillation, and chronic obstructive pulmonary disease were independently associated with good outcome. CONCLUSIONS: In this real-world series of patients with SMR undergoing TEER, a COAPT-ineligible profile was common. The presence of only 1 COAPT exclusion criterion or the absence of hemodynamic instability were associated with the most favourable outcomes.

Structural basis of cyclic oligoadenylate degradation by ancillary Type III CRISPR-Cas ring nucleases.

Type III CRISPR-Cas effector systems detect foreign RNA triggering DNA and RNA cleavage and synthesizing cyclic oligoadenylate molecules (cA) in their Cas10 subunit. cAs act as a second messenger activating auxiliary nucleases, leading to an indiscriminate RNA degradation that can end in cell dormancy or death. Standalone ring nucleases are CRISPR ancillary proteins which downregulate the strong immune response of Type III systems by degrading cA. These enzymes contain a CRISPR-associated Rossman-fold (CARF) domain, which binds and cleaves the cA molecule. Here, we present the structures of the standalone ring nuclease from Sulfolobus islandicus (Sis) 0811 in its apo and post-catalytic states. This enzyme is composed by a N-terminal CARF and a C-terminal wHTH domain. Sis0811 presents a phosphodiester hydrolysis metal-independent mechanism, which cleaves cA4 rings to generate linear adenylate species, thus reducing the levels of the second messenger and switching off the cell antiviral state. The structural and biochemical analysis revealed the coupling of a cork-screw conformational change with the positioning of key catalytic residues to proceed with cA4 phosphodiester hydrolysis in a non-concerted manner.

Autoimmune Myocarditis and Arrhythmogenic Mitral Valve Prolapse: An Unexpected Overlap Syndrome.

BACKGROUND: both myocarditis and mitral valve prolapse (MVP) are known uncommon causes of ventricular arrhythmias in young patients. AIM: to report the first clinical case of endomyocardial biopsy (EMB)-proven autoimmune myocarditis and associated arrhythmogenic MVP in a patient with recurrent ventricular fibrillation (VF) episodes. METHODS: myocarditis was diagnosed both by cardiac magnetic resonance (CMR) and EMB. Arrhythmogenic MVP was documented by transthoracic echocardiogram, CMR, and electroanatomical mapping of the trigger premature ventricular contractions (PVCs). RESULTS: a 22-year-old woman underwent immunosuppressive therapy after EMB-proven diagnosis of autoimmune myocarditis with VF onset and early implantable cardioverter defibrillator (ICD) placement. Three years later, she experienced two VF recurrences and persistent PVCs, despite no signs of myocarditis recurrence. An echocardiogram revealed bileaflet MVP with high arrhythmic risk features. Finally, electroanatomical mapping and ablation of the trigger PVC were successfully performed. CONCLUSION: in patients with recurrent VF episodes despite evidence-based medical treatment for myocarditis, MVP should be considered as an alternative arrhythmogenic substrate, and warrants early ICD implant and PVC-targeted therapy.